The Puzzlemaster Presents Vol. 2
Will Shortz
(Title shown below)

What remarkable little feature do the following words have in common?

1. Hire
2. Class
3. Weak
4. Mild
5. Brain
6. Backing
7. Elected
8. Waxing

Answer:

Changing a single letter in each word gives a new word opposite in meaning:

1. Hire - Fire
2. Class - Crass
3. Weak - Peak
4. Mild - Wild
5. Brain - Brawn
6. Backing - Bucking
7. Elected - Ejected
8. Waxing - Waning

Puzzle title: SMALL DIFFERENCE